From patchwork Mon May 18 12:09:19 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Raghavendra, Vignesh" X-Patchwork-Id: 473351 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id AC5D414016A for ; Mon, 18 May 2015 22:20:55 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753414AbbERMUy (ORCPT ); Mon, 18 May 2015 08:20:54 -0400 Received: from devils.ext.ti.com ([198.47.26.153]:38192 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752929AbbERMUw (ORCPT ); Mon, 18 May 2015 08:20:52 -0400 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by devils.ext.ti.com (8.13.7/8.13.7) with ESMTP id t4ICKHYX027622; Mon, 18 May 2015 07:20:17 -0500 Received: from DLEE71.ent.ti.com (dlee71.ent.ti.com [157.170.170.114]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id t4ICKGvB020228; Mon, 18 May 2015 07:20:16 -0500 Received: from dlep33.itg.ti.com (157.170.170.75) by DLEE71.ent.ti.com (157.170.170.114) with Microsoft SMTP Server id 14.3.224.2; Mon, 18 May 2015 07:20:16 -0500 Received: from uda0132425.apr.dhcp.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep33.itg.ti.com (8.14.3/8.13.8) with ESMTP id t4ICKBIJ006399; Mon, 18 May 2015 07:20:12 -0500 From: Vignesh R To: , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Evgeniy Polyakov , Jonathan Corbet CC: Tony Lindgren , Vignesh R , NeilBrown , Greg Kroah-Hartman , Fabian Frederick , , , Subject: [PATCH v2] w1: masters: omap_hdq: Add support for 1-wire mode Date: Mon, 18 May 2015 17:39:19 +0530 Message-ID: <1431950959-19606-1-git-send-email-vigneshr@ti.com> X-Mailer: git-send-email 1.9.1 MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org This patches makes following changes to omap_hdq driver - Enable 1-wire mode. - Implement w1_triplet callback to facilitate search rom procedure and auto detection of 1-wire slaves. - Proper enabling and disabling of interrupt. - Cleanups (formatting and return value checks). HDQ mode remains unchanged. Signed-off-by: Vignesh R --- v2: * report error if RX/TX_COMPLETE times out. Documentation/devicetree/bindings/w1/omap-hdq.txt | 7 +- Documentation/w1/masters/omap-hdq | 6 + drivers/w1/masters/omap_hdq.c | 224 ++++++++++++++++++---- 3 files changed, 203 insertions(+), 34 deletions(-) diff --git a/Documentation/devicetree/bindings/w1/omap-hdq.txt b/Documentation/devicetree/bindings/w1/omap-hdq.txt index fef794741bd1..913c5f91a0f9 100644 --- a/Documentation/devicetree/bindings/w1/omap-hdq.txt +++ b/Documentation/devicetree/bindings/w1/omap-hdq.txt @@ -1,11 +1,15 @@ * OMAP HDQ One wire bus master controller Required properties: -- compatible : should be "ti,omap3-1w" +- compatible : should be "ti,omap3-1w" or "ti,am4372-hdq" - reg : Address and length of the register set for the device - interrupts : interrupt line. - ti,hwmods : "hdq1w" +Optional properties: +- ti,mode: should be "hdq": HDQ mode "1w": one-wire mode. + If not specified HDQ mode is implied. + Example: - From omap3.dtsi @@ -14,4 +18,5 @@ Example: reg = <0x480b2000 0x1000>; interrupts = <58>; ti,hwmods = "hdq1w"; + ti,mode = "hdq"; }; diff --git a/Documentation/w1/masters/omap-hdq b/Documentation/w1/masters/omap-hdq index 884dc284b215..234522709a5f 100644 --- a/Documentation/w1/masters/omap-hdq +++ b/Documentation/w1/masters/omap-hdq @@ -44,3 +44,9 @@ e.g: insmod omap_hdq.ko W1_ID=2 inamod w1_bq27000.ko F_ID=2 +The driver also supports 1-wire mode. In this mode, there is no need to +pass slave ID as parameter. The driver will auto-detect slaves connected +to the bus using SEARCH_ROM procedure. 1-wire mode can be selected by +setting "ti,mode" property to "1w" in DT (see +Documentation/devicetree/bindings/w1/omap-hdq.txt for more details). +By default driver is in HDQ mode. diff --git a/drivers/w1/masters/omap_hdq.c b/drivers/w1/masters/omap_hdq.c index e7d448963a24..0e2f43bccf1f 100644 --- a/drivers/w1/masters/omap_hdq.c +++ b/drivers/w1/masters/omap_hdq.c @@ -17,6 +17,7 @@ #include #include #include +#include #include "../w1.h" #include "../w1_int.h" @@ -27,21 +28,23 @@ #define OMAP_HDQ_TX_DATA 0x04 #define OMAP_HDQ_RX_DATA 0x08 #define OMAP_HDQ_CTRL_STATUS 0x0c -#define OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK (1<<6) -#define OMAP_HDQ_CTRL_STATUS_CLOCKENABLE (1<<5) -#define OMAP_HDQ_CTRL_STATUS_GO (1<<4) -#define OMAP_HDQ_CTRL_STATUS_INITIALIZATION (1<<2) -#define OMAP_HDQ_CTRL_STATUS_DIR (1<<1) -#define OMAP_HDQ_CTRL_STATUS_MODE (1<<0) +#define OMAP_HDQ_CTRL_STATUS_SINGLE BIT(7) +#define OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK BIT(6) +#define OMAP_HDQ_CTRL_STATUS_CLOCKENABLE BIT(5) +#define OMAP_HDQ_CTRL_STATUS_GO BIT(4) +#define OMAP_HDQ_CTRL_STATUS_PRESENCE BIT(3) +#define OMAP_HDQ_CTRL_STATUS_INITIALIZATION BIT(2) +#define OMAP_HDQ_CTRL_STATUS_DIR BIT(1) #define OMAP_HDQ_INT_STATUS 0x10 -#define OMAP_HDQ_INT_STATUS_TXCOMPLETE (1<<2) -#define OMAP_HDQ_INT_STATUS_RXCOMPLETE (1<<1) -#define OMAP_HDQ_INT_STATUS_TIMEOUT (1<<0) +#define OMAP_HDQ_INT_STATUS_TXCOMPLETE BIT(2) +#define OMAP_HDQ_INT_STATUS_RXCOMPLETE BIT(1) +#define OMAP_HDQ_INT_STATUS_TIMEOUT BIT(0) #define OMAP_HDQ_SYSCONFIG 0x14 -#define OMAP_HDQ_SYSCONFIG_SOFTRESET (1<<1) -#define OMAP_HDQ_SYSCONFIG_AUTOIDLE (1<<0) +#define OMAP_HDQ_SYSCONFIG_SOFTRESET BIT(1) +#define OMAP_HDQ_SYSCONFIG_AUTOIDLE BIT(0) +#define OMAP_HDQ_SYSCONFIG_NOIDLE 0x0 #define OMAP_HDQ_SYSSTATUS 0x18 -#define OMAP_HDQ_SYSSTATUS_RESETDONE (1<<0) +#define OMAP_HDQ_SYSSTATUS_RESETDONE BIT(0) #define OMAP_HDQ_FLAG_CLEAR 0 #define OMAP_HDQ_FLAG_SET 1 @@ -67,6 +70,10 @@ struct hdq_data { * the data wrire or read. */ int init_trans; + int rrw; + /* mode: 0-HDQ 1-W1 */ + int mode; + }; static int omap_hdq_probe(struct platform_device *pdev); @@ -74,6 +81,7 @@ static int omap_hdq_remove(struct platform_device *pdev); static const struct of_device_id omap_hdq_dt_ids[] = { { .compatible = "ti,omap3-1w" }, + { .compatible = "ti,am4372-hdq" }, {} }; MODULE_DEVICE_TABLE(of, omap_hdq_dt_ids); @@ -90,15 +98,12 @@ static struct platform_driver omap_hdq_driver = { static u8 omap_w1_read_byte(void *_hdq); static void omap_w1_write_byte(void *_hdq, u8 byte); static u8 omap_w1_reset_bus(void *_hdq); -static void omap_w1_search_bus(void *_hdq, struct w1_master *master_dev, - u8 search_type, w1_slave_found_callback slave_found); static struct w1_bus_master omap_w1_master = { .read_byte = omap_w1_read_byte, .write_byte = omap_w1_write_byte, .reset_bus = omap_w1_reset_bus, - .search = omap_w1_search_bus, }; /* HDQ register I/O routines */ @@ -122,6 +127,15 @@ static inline u8 hdq_reg_merge(struct hdq_data *hdq_data, u32 offset, return new_val; } +static void hdq_disable_interrupt(struct hdq_data *hdq_data, u32 offset, + u32 mask) +{ + u32 ie; + + ie = readl(hdq_data->hdq_base + offset); + writel(ie & mask, hdq_data->hdq_base + offset); +} + /* * Wait for one or more bits in flag change. * HDQ_FLAG_SET: wait until any bit in the flag is set. @@ -229,13 +243,7 @@ static irqreturn_t hdq_isr(int irq, void *_hdq) return IRQ_HANDLED; } -/* HDQ Mode: always return success */ -static u8 omap_w1_reset_bus(void *_hdq) -{ - return 0; -} - -/* W1 search callback function */ +/* W1 search callback function in HDQ mode */ static void omap_w1_search_bus(void *_hdq, struct w1_master *master_dev, u8 search_type, w1_slave_found_callback slave_found) { @@ -262,9 +270,10 @@ static int _omap_hdq_reset(struct hdq_data *hdq_data) int ret; u8 tmp_status; - hdq_reg_out(hdq_data, OMAP_HDQ_SYSCONFIG, OMAP_HDQ_SYSCONFIG_SOFTRESET); + hdq_reg_out(hdq_data, OMAP_HDQ_SYSCONFIG, + OMAP_HDQ_SYSCONFIG_SOFTRESET); /* - * Select HDQ mode & enable clocks. + * Select HDQ/1W mode & enable clocks. * It is observed that INT flags can't be cleared via a read and GO/INIT * won't return to zero if interrupt is disabled. So we always enable * interrupt. @@ -282,7 +291,8 @@ static int _omap_hdq_reset(struct hdq_data *hdq_data) else { hdq_reg_out(hdq_data, OMAP_HDQ_CTRL_STATUS, OMAP_HDQ_CTRL_STATUS_CLOCKENABLE | - OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK); + OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK | + hdq_data->mode); hdq_reg_out(hdq_data, OMAP_HDQ_SYSCONFIG, OMAP_HDQ_SYSCONFIG_AUTOIDLE); } @@ -334,6 +344,18 @@ static int omap_hdq_break(struct hdq_data *hdq_data) ret = -ETIMEDOUT; goto out; } + + /* + * check for the presence detect bit to get + * set to show that the slave is responding + */ + if (!(hdq_reg_in(hdq_data, OMAP_HDQ_CTRL_STATUS) & + OMAP_HDQ_CTRL_STATUS_PRESENCE)) { + dev_dbg(hdq_data->dev, "Presence bit not set\n"); + ret = -ETIMEDOUT; + goto out; + } + /* * wait for both INIT and GO bits rerurn to zero. * zero wait time expected for interrupt mode. @@ -368,6 +390,8 @@ static int hdq_read_byte(struct hdq_data *hdq_data, u8 *val) goto out; } + hdq_data->hdq_irqstatus = 0; + if (!(hdq_data->hdq_irqstatus & OMAP_HDQ_INT_STATUS_RXCOMPLETE)) { hdq_reg_merge(hdq_data, OMAP_HDQ_CTRL_STATUS, OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO, @@ -400,7 +424,7 @@ rtn: } -/* Enable clocks and set the controller to HDQ mode */ +/* Enable clocks and set the controller to HDQ/1W mode */ static int omap_hdq_get(struct hdq_data *hdq_data) { int ret = 0; @@ -422,7 +446,7 @@ static int omap_hdq_get(struct hdq_data *hdq_data) pm_runtime_get_sync(hdq_data->dev); - /* make sure HDQ is out of reset */ + /* make sure HDQ/1W is out of reset */ if (!(hdq_reg_in(hdq_data, OMAP_HDQ_SYSSTATUS) & OMAP_HDQ_SYSSTATUS_RESETDONE)) { ret = _omap_hdq_reset(hdq_data); @@ -430,12 +454,13 @@ static int omap_hdq_get(struct hdq_data *hdq_data) /* back up the count */ hdq_data->hdq_usecount--; } else { - /* select HDQ mode & enable clocks */ + /* select HDQ/1W mode & enable clocks */ hdq_reg_out(hdq_data, OMAP_HDQ_CTRL_STATUS, OMAP_HDQ_CTRL_STATUS_CLOCKENABLE | - OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK); + OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK | + hdq_data->mode); hdq_reg_out(hdq_data, OMAP_HDQ_SYSCONFIG, - OMAP_HDQ_SYSCONFIG_AUTOIDLE); + OMAP_HDQ_SYSCONFIG_NOIDLE); hdq_reg_in(hdq_data, OMAP_HDQ_INT_STATUS); } } @@ -456,6 +481,8 @@ static int omap_hdq_put(struct hdq_data *hdq_data) if (ret < 0) return -EINTR; + hdq_reg_out(hdq_data, OMAP_HDQ_SYSCONFIG, + OMAP_HDQ_SYSCONFIG_AUTOIDLE); if (0 == hdq_data->hdq_usecount) { dev_dbg(hdq_data->dev, "attempt to decrement use count" " when it is zero"); @@ -471,6 +498,100 @@ static int omap_hdq_put(struct hdq_data *hdq_data) return ret; } +/* + * W1 triplet callback function - used for searching ROM addresses. + * Registered only when controller is in 1-wire mode. + */ +static u8 omap_w1_triplet(void *_hdq, u8 bdir) +{ + u8 id_bit, comp_bit; + int err; + u8 ret = 0x3; /* no slaves responded */ + struct hdq_data *hdq_data = _hdq; + u8 ctrl = OMAP_HDQ_CTRL_STATUS_SINGLE | OMAP_HDQ_CTRL_STATUS_GO | + OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK; + u8 mask = ctrl | OMAP_HDQ_CTRL_STATUS_DIR; + + omap_hdq_get(_hdq); + + err = mutex_lock_interruptible(&hdq_data->hdq_mutex); + if (err < 0) { + dev_dbg(hdq_data->dev, "Could not acquire mutex\n"); + goto rtn; + } + + hdq_data->hdq_irqstatus = 0; + /* read id_bit */ + hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS, + ctrl | OMAP_HDQ_CTRL_STATUS_DIR, mask); + err = wait_event_timeout(hdq_wait_queue, + (hdq_data->hdq_irqstatus + & OMAP_HDQ_INT_STATUS_RXCOMPLETE), + OMAP_HDQ_TIMEOUT); + if (err == 0) { + dev_dbg(hdq_data->dev, "RX wait elapsed\n"); + goto out; + } + id_bit = (hdq_reg_in(_hdq, OMAP_HDQ_RX_DATA) & 0x01); + + hdq_data->hdq_irqstatus = 0; + /* read comp_bit */ + hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS, + ctrl | OMAP_HDQ_CTRL_STATUS_DIR, mask); + err = wait_event_timeout(hdq_wait_queue, + (hdq_data->hdq_irqstatus + & OMAP_HDQ_INT_STATUS_RXCOMPLETE), + OMAP_HDQ_TIMEOUT); + if (err == 0) { + dev_dbg(hdq_data->dev, "RX wait elapsed\n"); + goto out; + } + comp_bit = (hdq_reg_in(_hdq, OMAP_HDQ_RX_DATA) & 0x01); + + if (id_bit && comp_bit) { + ret = 0x03; /* no slaves responded */ + goto out; + } + if (!id_bit && !comp_bit) { + /* Both bits are valid, take the direction given */ + ret = bdir ? 0x04 : 0; + } else { + /* Only one bit is valid, take that direction */ + bdir = id_bit; + ret = id_bit ? 0x05 : 0x02; + } + + /* write bdir bit */ + hdq_reg_out(_hdq, OMAP_HDQ_TX_DATA, bdir); + hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS, ctrl, mask); + err = wait_event_timeout(hdq_wait_queue, + (hdq_data->hdq_irqstatus + & OMAP_HDQ_INT_STATUS_TXCOMPLETE), + OMAP_HDQ_TIMEOUT); + if (err == 0) { + dev_dbg(hdq_data->dev, "TX wait elapsed\n"); + goto out; + } + + hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS, 0, + OMAP_HDQ_CTRL_STATUS_SINGLE); + +out: + mutex_unlock(&hdq_data->hdq_mutex); +rtn: + omap_hdq_put(_hdq); + return ret; +} + +/* reset callback */ +static u8 omap_w1_reset_bus(void *_hdq) +{ + omap_hdq_get(_hdq); + omap_hdq_break(_hdq); + omap_hdq_put(_hdq); + return 0; +} + /* Read a byte of data from the device */ static u8 omap_w1_read_byte(void *_hdq) { @@ -478,6 +599,10 @@ static u8 omap_w1_read_byte(void *_hdq) u8 val = 0; int ret; + /* First write to initialize the transfer */ + if (hdq_data->init_trans == 0) + omap_hdq_get(hdq_data); + ret = hdq_read_byte(hdq_data, &val); if (ret) { ret = mutex_lock_interruptible(&hdq_data->hdq_mutex); @@ -491,6 +616,10 @@ static u8 omap_w1_read_byte(void *_hdq) return -1; } + hdq_disable_interrupt(hdq_data, OMAP_HDQ_CTRL_STATUS, + ~OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK); + hdq_data->hdq_usecount = 0; + /* Write followed by a read, release the module */ if (hdq_data->init_trans) { ret = mutex_lock_interruptible(&hdq_data->hdq_mutex); @@ -517,6 +646,14 @@ static void omap_w1_write_byte(void *_hdq, u8 byte) if (hdq_data->init_trans == 0) omap_hdq_get(hdq_data); + /* + * We need to reset the slave before + * issuing the SKIP ROM command, else + * the slave will not work. + */ + if (byte == W1_SKIP_ROM) + omap_hdq_break(hdq_data); + ret = mutex_lock_interruptible(&hdq_data->hdq_mutex); if (ret < 0) { dev_dbg(hdq_data->dev, "Could not acquire mutex\n"); @@ -551,6 +688,7 @@ static int omap_hdq_probe(struct platform_device *pdev) struct resource *res; int ret, irq; u8 rev; + const char *mode; hdq_data = devm_kzalloc(dev, sizeof(*hdq_data), GFP_KERNEL); if (!hdq_data) { @@ -567,10 +705,21 @@ static int omap_hdq_probe(struct platform_device *pdev) return PTR_ERR(hdq_data->hdq_base); hdq_data->hdq_usecount = 0; + hdq_data->rrw = 0; mutex_init(&hdq_data->hdq_mutex); pm_runtime_enable(&pdev->dev); - pm_runtime_get_sync(&pdev->dev); + ret = pm_runtime_get_sync(&pdev->dev); + if (ret < 0) { + dev_dbg(&pdev->dev, "pm_runtime_get_sync failed\n"); + goto err_w1; + } + + ret = _omap_hdq_reset(hdq_data); + if (ret) { + dev_dbg(&pdev->dev, "reset failed\n"); + return -EINVAL; + } rev = hdq_reg_in(hdq_data, OMAP_HDQ_REVISION); dev_info(&pdev->dev, "OMAP HDQ Hardware Rev %c.%c. Driver in %s mode\n", @@ -594,6 +743,15 @@ static int omap_hdq_probe(struct platform_device *pdev) pm_runtime_put_sync(&pdev->dev); + ret = of_property_read_string(pdev->dev.of_node, "ti,mode", &mode); + if (ret < 0 || !strcmp(mode, "hdq")) { + hdq_data->mode = 0; + omap_w1_master.search = omap_w1_search_bus; + } else { + hdq_data->mode = 1; + omap_w1_master.triplet = omap_w1_triplet; + } + omap_w1_master.data = hdq_data; ret = w1_add_master_device(&omap_w1_master); @@ -635,8 +793,8 @@ static int omap_hdq_remove(struct platform_device *pdev) module_platform_driver(omap_hdq_driver); module_param(w1_id, int, S_IRUSR); -MODULE_PARM_DESC(w1_id, "1-wire id for the slave detection"); +MODULE_PARM_DESC(w1_id, "1-wire id for the slave detection in HDQ mode"); MODULE_AUTHOR("Texas Instruments"); -MODULE_DESCRIPTION("HDQ driver Library"); +MODULE_DESCRIPTION("HDQ-1W driver Library"); MODULE_LICENSE("GPL");